(1) Field of the Invention
The invention relates to underwater vehicles having sonar arrays therein, and is directed more particularly to a nose cone for attachment to a test vehicle to shield the sonar array from acoustic pressure so that noise resulting solely from structural vibration of the vehicle can be determined.
(2) Description of the Prior Art
It is known to provide underwater vehicles, such as torpedoes, with sonar arrays adapted to receive noise from a water environment and to lock in on a portion of such noise for possible target acquisition. However, the noise received by the array is a combination of acoustic pressures in the water and noise generated by vehicle structural vibration reaching the array through the array support structure. There is a need for means by which the structural noise can be isolated and measured.